This invention relates generally to turbojet engines and more particularly to such engines employing liquid as a motive flow medium. Engines of this type are covered in my prior U.S. Pat. Nos. 4,646,515 and 4,897,995, the disclosures of which are incorporated herein by reference.
According to my earlier U.S. Pat. No. 4,646,515, a motive liquid such as water flows through an annular passage within an engine, said passage forming a rotating conduit between rotor blading and stationary walls of the engine housing. Flow sections of the conduit form a centrifugal pump at the inlet end and a centrifugal turbine at the exit end of the conduit. Pump and turbine portions of the blading are fixedly mounted on a common rotor shaft which also mounts axial blades forming the combustion section within the conduit axially spacing the pump and turbine flow sections. Bubbles of a combustible gas are introduced into the flow of liquid through the conduit at the inlet end for sequential compression, ignition and expansion as the gas bubbles are carried in the motive liquid through the pump, combustion and turbine sections of the flow conduit. Flow exiting the turbine section of the conduit is recycled to the pump section while exhaust gases in the bubbles are drawn and expelled through a passage in the rotor shaft.
According to my later U.S. Pat. No. 4,897,995, the burned bubbles of gas are exhausted with the motive liquid from the turbine flow section at the exit end of the conduit.
It is an important object of the present invention to provide an engine of the foregoing type which is more suitable for underwater applications, where light weight, small size, high power output and high speeds are essential.